->  PQ> Ahh... but is it sand and dust flowing as if in a fluid motion? 
 
-> That's what I `saw' when their photos reached me - very common  
-> sight in the sand dunes at my favourite beach... 
 
-> Time will tell, no doubt. 
 
-> Miles. 
  
Sand and dust does that partly because air or other fluid gets between 
the grains as they're moving, acting as a lubricant. It might not work 
in the very rarified atmosphere of Mars. 
  
                                dow 
--- Platinum Xpress/Win/WINServer v3.0pr5